A corrugating machine as a corrugated cardboard sheet manufacturing apparatus includes a single facer that forms a single-face corrugated cardboard sheet and a double facer that forms a double-face corrugated cardboard sheet by gluing bottom liner board paper to a single-face corrugated cardboard sheet. The single facer corrugates a corrugating medium that is fed from a mill roll stand, and forms a single-face corrugated cardboard sheet by gluing a top liner board, which is fed from another mill roll stand, to the corrugating medium. The single-face corrugated cardboard sheet, which is formed by the single facer, is sent to a bridge provided on the downstream side, and is sent to a double facer, which is provided on the downstream side, according to the speed thereof while being stored in the double facer. The double facer forms a double-face corrugated cardboard sheet by gluing a bottom liner board, which is sent from a separate mill roll stand, to the single-face corrugated cardboard sheet sent from the bridge. After predetermined slits or ruled lines are formed on the double-face corrugated cardboard sheet, which has passed through the double facer, in a conveying direction by a slitter scorer, the double-face corrugated cardboard sheet forms corrugated cardboard sheets by being cut in the width direction with a cutoff. The corrugated cardboard sheets are stacked on a stacker, and are sequentially discharged.
A bottom liner board is glued to the single-face corrugated cardboard sheet, which is formed by the single facer, by the double facer, so that the double-face corrugated cardboard sheet is formed. Accordingly, the corrugating machine is provided with an adhesive application device that applies adhesive liquid to apex portions of corrugated portions of the single-face corrugating medium (the single-face corrugated cardboard sheet). The adhesive application device applies adhesive liquid, which is stored in an adhesive liquid tank, to an adhesive application roller, and can transfer the adhesive liquid, which is applied to the adhesive application roller, to the apex portions of corrugated portions of the single-face corrugated cardboard sheet after adjusting the thickness of the adhesive liquid, which is applied to the adhesive application roller, to a set thickness by a doctor roller.
In this case, the width of the adhesive liquid, which is applied to the single-face corrugated cardboard sheet by the adhesive application device, needs to be adjusted according to the width of the bottom liner board that is to be glued to the single-face corrugated cardboard sheet. When the width of the adhesive liquid applied to the single-face corrugated cardboard sheet is not a width according to the width of the bottom liner board, the adhesive liquid is extruded from end portions of the bottom liner board. Accordingly, when the single-face corrugated cardboard sheet and the bottom liner board are sent to the double facer and travel on a hot plate, the adhesive liquid is applied to the hot plate and is solidified. For this reason, there is a concern that a single-face corrugated cardboard sheet and a bottom liner board to be subsequently conveyed may be damaged.
For example, there are means disclosed in the following PTLs as means for solving the problem. A liquid transfer device disclosed in PTL 1 includes a doctor roller that scrapes off surplus liquid applied to an applicator roller, a pair of damming plates that are spaced apart from each other in the axial direction of the applicator roller, and regulating parts that are provided on the damming plates and commonly come into contact with the peripheral surfaces of both the rollers facing each other. Further, an adhesive application method and an adhesive application device of a corrugated cardboard manufacturing apparatus disclosed in PTL 2 include dam plates that are provided on the upstream side of a doctor roller and adjust the thickness of adhesive liquid of a region inside an end of a single-face corrugated cardboard sheet, and elastic scrapers that are provided on the downstream side of the dam plates and remove adhesive liquid in a region inside an end of the single-face corrugated cardboard sheet.